Scale the emulated event in EventSender when use-zoom-for-dsf is enabled

content/public/test/layouttest_support.h

Index: content/public/test/layouttest_support.h
diff --git a/content/public/test/layouttest_support.h b/content/public/test/layouttest_support.h
index 325b51367f2f1778ac046921ea60e5f3f59abdad..7a6a27e86cc4752ba7619cdfbad1b7adeb8a5224 100644
--- a/content/public/test/layouttest_support.h
+++ b/content/public/test/layouttest_support.h
@@ -113,6 +113,9 @@ void ForceResizeRenderView(RenderView* render_view,
 // Set the device scale factor and force the compositor to resize.
 void SetDeviceScaleFactor(RenderView* render_view, float factor);
 
+// Get the window to viewport scale.
+float GetWindowToViewportScale(RenderView* render_view);
+
 // Set the device color profile associated with the profile |name|.
 void SetDeviceColorProfile(RenderView* render_view, const std::string& name);